The document provides an overview of iOS development, discussing its architecture, key components like Cocoa Touch and the MVC design pattern, and essential tools like Xcode and Objective-C. It highlights the consistent interface across devices and the strong control Apple maintains over the ecosystem. The document also covers the basics of app structure, including view controllers, storyboards, and navigation types.

1. Sasha Goldshtein
CTO, SELA Group
@goldshtn
blog.sashag.net
First Steps in iOS
Development
© Copyright SELA software & Education Labs Ltd. | 14-18 Baruch Hirsch St Bnei Brak, 51202 Israel | www.selagroup.com

2. The iOS Platform
Apps
• 877,013+ of them 
Cocoa
Touch
• UI, gestures, view
navigation, media
Core Services
• Location,
threading, HTTP
Darwin (kernel)
• Drivers,
security

3. Platform Philosophy
User
Developer
Apple
• Consistent
interface
metaphors
• Always at
home, on any
device and in
any app
• Seamless
sync, backup,
purchase
• Strong push
to object
orientation
• Just one
language
(Objective C)
• Strong
separation of
concerns in
UI – MVC
• Full control
over the
ecosystem,
hardware and
software
• Ultimate
arbitrator on
whether an
app is a fit for
the App Store

4. iOS Devices and Versions
September 2013:
≈95% of iOS devices
run iOS 6
iPhone
3GS
• iOS 3
• iOS 4
Original
iPad
iPhone 5
iPhone
4/4S
• iOS 5
• iOS 6
iPhone
5c/5s
• iOS 7

5. Devices and Resolutions
iPhone
3/3GS
iPhone
4/4S
iPhone
5/5c/5s
iPad
1/2
iPad
Mini
iPad
3/4
3.5”
3.5”
4”
9.7”
7.9”
9.7”
320 480
640 960
640 1136
1024 768
1024 768
2048 153
6

6. Developing for iOS
UIKit
Xcode
Objective
C
self.title = [NSString initWithFormat:@"%d", n];
[button setTitle:self.title forState:UIControlStateNormal];

7. Our First iOS App
Demo

8. Project Components
Generated files:
Application delegate
Initial view controller
Main storyboard
Property list
File for localizable strings
Application icons
Xcode also adds basic
frameworks to your app

9. iOS MVC Fundamentals
View
• Draws itself
on the
screen
• Contains
generic UIrelated data
View
Controller
• Creates and
coordinates
views
• Populates
views and
reflects
changes to
the model
Model
• UI-agnostic
classes
• Can be a
bunch of
objects, a
database, a
file, an
Internet
service

10. Outlets and Actions
Xcode connects views and controllers
Controller manipulates views through outlets
Controller receives events through actions
@interface MyViewController : UIViewController
@property (nonatomic, weak) IBOutlet UITextField *petName;
- (IBAction)getQuote;
@end

11. Connecting UI to Code
Demo

12. iOS Navigation Types
Tab bar controller
Navigation controller

13. Storyboards
The storyboard describes your application’s
view controllers and connects them with
segues

14. Passing Parameters
Usually the source view controller sets
properties or calls methods on the destination
view controller
- (void)prepareForSegue:(UIStoryboardSegue *)segue
sender:(id)sender
{
MySecondVC *vc = segue.destinationViewController;
vc.itemToDisplay = [self selectedItem];
vc.delegate = self; // For callbacks
}

15. Storyboards and Segues
Demo

16. Summary
Objective C fundamentals
View controllers, views, outlets, actions
Storyboards, segues
It’s just another
{language, IDE, UI framework}
The rest is just details: data, networking,
settings, table views, styling, …

17. Questions
Sasha Goldshtein
CTO, SELA Group
@goldshtn
blog.sashag.net